the Mega Card is now a thing :D
it was made possible with megadrive guru Tiido's help […]
the Mega Card is now a thing 😁
it was made possible with megadrive guru Tiido's help
so what is onboard?
- ALS100 soundchip providing SB/SBPRO/SB16 compatibility
- a Yamaha OPL3
- Realtek 8019AS ehternet controller providing 10mbps connection and boot rom support for XT-IDE BIOS
- a scandoubler that makes possible for the onboard megadrive to output a standard VGA signal (it is a linedoubler like old amiga scandoublers, no framebuffer no lag - 1 scanline delay) , has jumper to enable/disable scanlines
- an optional exclusive Serdaco MIDI daughterboard - the X3GS (basically same as X2GS but green and has some leds for added bling 🤣)
- ISA header and MIDI I/O + routing configuration for an upcoming PCMIDI upgrade daughterboard , there are 2 midi jacks on board: 1x OUT and 1x IN/OUT selectable via jumpers
The ALS100 is a nice chip (and rare/expensive for some reason) but it cannot escape it's budget card roots. Rest assured this is the best sounding ALS100 card out there but do not expect quality to blow your mind.
It goes hand-in-hand with the Mega-PC that is a noisy and crammed system 🤣
The chip does support all SB ADPCM modes so there are no missing sounds in older games that use them.
The onboard Amstrad Adlib needs to be disabled with a simple mod - else the ALS100 software will complain about Adlib ports being used. Completely optional one can ignore that and edit ALS.INI by hand if needed.
The megadrive sound is routed through ALS100 so no separate speakers or external connections needed.
The scandoubler portion is now as good as it gets with the signals it gets from the original amstrad megadrive card - which is a little messy: video signal routing is not good and RGB levels overdriven.
Despite that, the photos below do not do it justice: at times one might think it's an emulator running and not the actual megadrive.
The ribbon cable from the amstrad megadrive card connects to Mega Card and then a new ribbon cable connects to the Amstrad motherboard. This way the original VGA port is used and A/V switching is done on the Mega Card.
There will be research how to mod the original amstrad megadrive card to bypass it's shortcomings: it will be quite some components removed but if someone wants to get the max quality out of it then it will be an option.
A small cable is needed to patch the megadrive clock to the scandoubler, this cannot be avoided and will look like this , solder points are 2 legs of the crystal oscillator...
and here is how the card connects to the system:
and now some pics of the card in action 😀 keep in mind I cannot take good CRT photos for the life of me, my camera has especially troubles with color balance 😐
that's it for now! hope you like what you see
I am not sure what IMGUR will do to the 11mb JPGs but I managed to get better crt pics 😀
I suggest you click on the direct links to get the full resolution of the pics